fix: chain reorg now copes with null blocks

Author: Westlad

nightfall-client/src/event-handlers/block-proposed.mjs

@@ -84,7 +84,7 @@ async function blockProposedEventHandler(data) {
 // await Promise.all(toStore);
 await Promise.all(dbUpdates);
 const updatedTimber = Timber.statelessUpdate(latestTree, blockCommitments);
-await saveTree(data.blockNumber, block.blockNumberL2, updatedTimber);
+await saveTree(transactionHashL1, block.blockNumberL2, updatedTimber);
 logger.debug(`Saved tree for L2 block ${block.blockNumberL2}`);
 await Promise.all(
 // eslint-disable-next-line consistent-return

nightfall-client/src/event-handlers/chain-reorg.mjs

@@ -16,7 +16,7 @@ import {
 } from '../services/commitment-storage.mjs';
 import {
 getBlockByTransactionHashL1,
-deleteTreeByBlockNumberL2,
+deleteTreeByTransactionHashL1,
 clearBlockNumberL1ForBlock,
 } from '../services/database.mjs';
 
@@ -42,14 +42,12 @@ async function removeBlockProposedEventHandler(eventObject) {
 // so find out which L2 block has been removed by this event removal.
 logger.debug(`Looking for block with transactionHash, ${transactionHash}`);
 const block = await getBlockByTransactionHashL1(transactionHash);
-if (block) logger.debug(`Found L2 block ${block.blockNumberL2}`);
-else throw new Error(`Could not find L2 block with L1 transactionHash, ${transactionHash}`);
-// then we delete the Timber record associated with this block
-const res = await deleteTreeByBlockNumberL2(block.blockNumberL2);
-logger.debug(`Deleted tree with block number ${block.blockNumberL2}, ${res}`);
 // now we can clear the L1 blocknumber to indicate that the L2 block is no longer
-// on chain.
-return clearBlockNumberL1ForBlock(eventObject.transactionHash);
+// on chain (if it's a block that we have saved)
+if (block) await clearBlockNumberL1ForBlock(transactionHash);
+// then we delete the Timber record associated with this block
+logger.debug(`Deleting tree with proposeBlock transactionHash ${transactionHash}`);
+return deleteTreeByTransactionHashL1(transactionHash);
 }
 
 export default removeBlockProposedEventHandler;

nightfall-client/src/services/database.mjs

@@ -22,11 +22,11 @@ const {
 Timber functions
 */
 
-export async function saveTree(blockNumber, blockNumberL2, timber) {
+export async function saveTree(transactionHashL1, blockNumberL2, timber) {
 const connection = await mongo.connection(MONGO_URL);
 const db = connection.db(COMMITMENTS_DB);
 return db.collection(TIMBER_COLLECTION).insertOne({
-_id: blockNumber,
+_id: transactionHashL1,
 blockNumberL2,
 frontier: timber.frontier,
 leafCount: timber.leafCount,
@@ -75,6 +75,12 @@ export async function deleteTreeByBlockNumberL2(blockNumberL2) {
 return db.collection(TIMBER_COLLECTION).deleteMany({ blockNumberL2: { $gte: blockNumberL2 } });
 }
 
+export async function deleteTreeByTransactionHashL1(transactionHashL1) {
+const connection = await mongo.connection(MONGO_URL);
+const db = connection.db(COMMITMENTS_DB);
+return db.collection(TIMBER_COLLECTION).deleteOne({ transactionHashL1 });
+}
+
 /**
 Blocks Collection
 */

test/ping-pong/user-local/src/index.mjs

@@ -69,22 +69,26 @@ async function localTest() {
 }
 await nf3.deposit(ercAddress, tokenType, value, tokenId);
 await new Promise(resolve => setTimeout(resolve, TX_WAIT)); // this may need to be longer on a real blockchain
+console.log(`Completed ${i + 1} pings`);
 }
 
 // Wait for sometime at the end to retrieve balance to include any transactions sent by the other use
 // This needs to be much longer than we may have waited for a transfer
-await new Promise(resolving => setTimeout(resolving, 20 * TX_WAIT)); // TODO get balance waiting working well
-const endBalance = await retrieveL2Balance(nf3);
-
-if (endBalance - startBalance === 2 * value + value * TEST_LENGTH) {
-logger.info('Test passed');
-logger.info('Balance of User (2*value (2*1) + value received) ', endBalance - startBalance);
-logger.info('Amount sent to other User', value * TEST_LENGTH);
-nf3.close();
-} else {
-logger.info('The test failed because the L2 balance has not increased');
-process.exit(1);
-}
+let loop = 0;
+do {
+const endBalance = await retrieveL2Balance(nf3);
+if (endBalance - startBalance === 2 * value + value * TEST_LENGTH) {
+logger.info('Test passed');
+logger.info('Balance of User (2*value (2*1) + value received) ', endBalance - startBalance);
+logger.info('Amount sent to other User', value * TEST_LENGTH);
+nf3.close();
+break;
+} else {
+logger.info('The test has not yet passed because the L2 balance has not increased - waiting');
+await new Promise(resolving => setTimeout(resolving, 20 * TX_WAIT)); // TODO get balance waiting working well
+loop++;
+}
+} while (loop < 10);
 }
 
 localTest();